Heterostructured design and microcrack management mitigate the strength-ductility dilemma in metallic materials. Here

we demonstrate a simultaneous enhancement of strength and ductility in graphene-decorated bimodal pure nickel

achieving a strength increase to 1 GPa and an 18% improvement in elongation by designing heterostructure with graphene

metal powders

and metal foams. The results show that grain refinement

hetero-deformation-induced hardening

and activated stacking faults mainly cause the strength-ductility synergy. Additionally

while dispersed microcracks nucleate within the fine grain zones

their propagation is constrained by the coarse grain zones. This study provides new insights into improving the strength-ductility combination in metallic materials.